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sed or awk: delete n lines following a pattern
...
Explanation:
-v regex="$regex" -v count="$count" defines awk variables based on shell variables of the same name.
$0 ~ regex matches the line of interest
{ skip=count; next } initializes the skip count and proceeds to the next line, effectively skipping the matching line; in the 2nd solution, t...
MySql Table Insert if not exist otherwise update
...me=[hash_name]) l
limit 1;
This example is cribbed from one of my databases, with the input parameters (two names and a number) replaced with [hasher_name], [hash_name], and [new_value]. The nested SELECT...LIMIT 1 pulls the first of either the existing record or a new record (last_recogs.id i...
What are the differences between the threading and multiprocessing modules?
...nd a thread pool like this:
with concurrent.futures.ThreadPoolExecutor(max_workers=4) as executor:
executor.submit(job, argument)
executor.map(some_function, collection_of_independent_things)
# ...
You can even get the results of those jobs and pass them on to further jobs, wait for t...
warning about too many open figures
...) will remove a specific figure instance from the pylab state machine (plt._pylab_helpers.Gcf) and allow it to be garbage collected.
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Comparing strings with == which are declared final in Java
...llowing byte code:
Code:
0: ldc #2; //String str
2: astore_1
3: ldc #3; //String ing
5: astore_2
6: new #4; //class java/lang/StringBuilder
9: dup
10: invokespecial #5; //Method java/lang/StringBuilder."<init>":()V
13: aload_1
14: invo...
How would you count occurrences of a string (actually a char) within a string?
...ed.
Also, for multicharacter substring you should use the following code (based on Richard Watson's solution)
int count = 0, n = 0;
if(substring != "")
{
while ((n = source.IndexOf(substring, n, StringComparison.InvariantCulture)) != -1)
{
n += substring.Length;
++count;
...
Android preferences onclick event
...z am getting ActivityNotFoundException :(
– theapache64
Feb 8 '16 at 17:01
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...
Adding Core Data to existing iPhone project
...
All the CoreData header files are imported in App_Prefix.pch, so the CoreData classes will be available throughout your Project, so you don't have to manually import the header in the files you need them.
So open up Xcode and look for some file like App_Prefix.pch, by defa...
Git: How to remove file from historical commit?
...refs.
The filter-branch approach is considerably more powerful than the rebase approach, since it
allows you to work on all branches/refs at once,
renames any tags on the fly
operates cleanly even if there have been several merge commits since the addition of the file
operates cleanly even if t...
How to rename items in values() in Django?
... could use the extra method:
MyModel.objects.extra(
select={
'renamed_value': 'cryptic_value_name'
}
).values(
'renamed_value'
)
This basically does SELECT cryptic_value_name AS renamed_value in the SQL.
Another option, if you always want the renamed version but the db has the cryptic nam...